Andrew's git - gitweb.git/blob - builtin/name-rev.c

   1#include "builtin.h"
   2#include "cache.h"
   3#include "config.h"
   4#include "commit.h"
   5#include "tag.h"
   6#include "refs.h"
   7#include "parse-options.h"
   8#include "sha1-lookup.h"
   9#include "commit-slab.h"
  10
  11#define CUTOFF_DATE_SLOP 86400 /* one day */
  12
  13typedef struct rev_name {
  14        const char *tip_name;
  15        timestamp_t taggerdate;
  16        int generation;
  17        int distance;
  18        int from_tag;
  19} rev_name;
  20
  21define_commit_slab(commit_rev_name, struct rev_name *);
  22
  23static timestamp_t cutoff = TIME_MAX;
  24static struct commit_rev_name rev_names;
  25
  26/* How many generations are maximally preferred over _one_ merge traversal? */
  27#define MERGE_TRAVERSAL_WEIGHT 65535
  28
  29static struct rev_name *get_commit_rev_name(struct commit *commit)
  30{
  31        struct rev_name **slot = commit_rev_name_peek(&rev_names, commit);
  32
  33        return slot ? *slot : NULL;
  34}
  35
  36static void set_commit_rev_name(struct commit *commit, struct rev_name *name)
  37{
  38        *commit_rev_name_at(&rev_names, commit) = name;
  39}
  40
  41static int is_better_name(struct rev_name *name,
  42                          const char *tip_name,
  43                          timestamp_t taggerdate,
  44                          int generation,
  45                          int distance,
  46                          int from_tag)
  47{
  48        /*
  49         * When comparing names based on tags, prefer names
  50         * based on the older tag, even if it is farther away.
  51         */
  52        if (from_tag && name->from_tag)
  53                return (name->taggerdate > taggerdate ||
  54                        (name->taggerdate == taggerdate &&
  55                         name->distance > distance));
  56
  57        /*
  58         * We know that at least one of them is a non-tag at this point.
  59         * favor a tag over a non-tag.
  60         */
  61        if (name->from_tag != from_tag)
  62                return from_tag;
  63
  64        /*
  65         * We are now looking at two non-tags.  Tiebreak to favor
  66         * shorter hops.
  67         */
  68        if (name->distance != distance)
  69                return name->distance > distance;
  70
  71        /* ... or tiebreak to favor older date */
  72        if (name->taggerdate != taggerdate)
  73                return name->taggerdate > taggerdate;
  74
  75        /* keep the current one if we cannot decide */
  76        return 0;
  77}
  78
  79static void name_rev(struct commit *commit,
  80                const char *tip_name, timestamp_t taggerdate,
  81                int generation, int distance, int from_tag,
  82                int deref)
  83{
  84        struct rev_name *name = get_commit_rev_name(commit);
  85        struct commit_list *parents;
  86        int parent_number = 1;
  87        char *to_free = NULL;
  88
  89        parse_commit(commit);
  90
  91        if (commit->date < cutoff)
  92                return;
  93
  94        if (deref) {
  95                tip_name = to_free = xstrfmt("%s^0", tip_name);
  96
  97                if (generation)
  98                        die("generation: %d, but deref?", generation);
  99        }
 100
 101        if (name == NULL) {
 102                name = xmalloc(sizeof(rev_name));
 103                set_commit_rev_name(commit, name);
 104                goto copy_data;
 105        } else if (is_better_name(name, tip_name, taggerdate,
 106                                  generation, distance, from_tag)) {
 107copy_data:
 108                name->tip_name = tip_name;
 109                name->taggerdate = taggerdate;
 110                name->generation = generation;
 111                name->distance = distance;
 112                name->from_tag = from_tag;
 113        } else {
 114                free(to_free);
 115                return;
 116        }
 117
 118        for (parents = commit->parents;
 119                        parents;
 120                        parents = parents->next, parent_number++) {
 121                if (parent_number > 1) {
 122                        size_t len;
 123                        char *new_name;
 124
 125                        strip_suffix(tip_name, "^0", &len);
 126                        if (generation > 0)
 127                                new_name = xstrfmt("%.*s~%d^%d", (int)len, tip_name,
 128                                                   generation, parent_number);
 129                        else
 130                                new_name = xstrfmt("%.*s^%d", (int)len, tip_name,
 131                                                   parent_number);
 132
 133                        name_rev(parents->item, new_name, taggerdate, 0,
 134                                 distance + MERGE_TRAVERSAL_WEIGHT,
 135                                 from_tag, 0);
 136                } else {
 137                        name_rev(parents->item, tip_name, taggerdate,
 138                                 generation + 1, distance + 1,
 139                                 from_tag, 0);
 140                }
 141        }
 142}
 143
 144static int subpath_matches(const char *path, const char *filter)
 145{
 146        const char *subpath = path;
 147
 148        while (subpath) {
 149                if (!wildmatch(filter, subpath, 0))
 150                        return subpath - path;
 151                subpath = strchr(subpath, '/');
 152                if (subpath)
 153                        subpath++;
 154        }
 155        return -1;
 156}
 157
 158static const char *name_ref_abbrev(const char *refname, int shorten_unambiguous)
 159{
 160        if (shorten_unambiguous)
 161                refname = shorten_unambiguous_ref(refname, 0);
 162        else if (starts_with(refname, "refs/heads/"))
 163                refname = refname + 11;
 164        else if (starts_with(refname, "refs/"))
 165                refname = refname + 5;
 166        return refname;
 167}
 168
 169struct name_ref_data {
 170        int tags_only;
 171        int name_only;
 172        struct string_list ref_filters;
 173        struct string_list exclude_filters;
 174};
 175
 176static struct tip_table {
 177        struct tip_table_entry {
 178                struct object_id oid;
 179                const char *refname;
 180        } *table;
 181        int nr;
 182        int alloc;
 183        int sorted;
 184} tip_table;
 185
 186static void add_to_tip_table(const struct object_id *oid, const char *refname,
 187                             int shorten_unambiguous)
 188{
 189        refname = name_ref_abbrev(refname, shorten_unambiguous);
 190
 191        ALLOC_GROW(tip_table.table, tip_table.nr + 1, tip_table.alloc);
 192        oidcpy(&tip_table.table[tip_table.nr].oid, oid);
 193        tip_table.table[tip_table.nr].refname = xstrdup(refname);
 194        tip_table.nr++;
 195        tip_table.sorted = 0;
 196}
 197
 198static int tipcmp(const void *a_, const void *b_)
 199{
 200        const struct tip_table_entry *a = a_, *b = b_;
 201        return oidcmp(&a->oid, &b->oid);
 202}
 203
 204static int name_ref(const char *path, const struct object_id *oid, int flags, void *cb_data)
 205{
 206        struct object *o = parse_object(oid);
 207        struct name_ref_data *data = cb_data;
 208        int can_abbreviate_output = data->tags_only && data->name_only;
 209        int deref = 0;
 210        timestamp_t taggerdate = TIME_MAX;
 211
 212        if (data->tags_only && !starts_with(path, "refs/tags/"))
 213                return 0;
 214
 215        if (data->exclude_filters.nr) {
 216                struct string_list_item *item;
 217
 218                for_each_string_list_item(item, &data->exclude_filters) {
 219                        if (subpath_matches(path, item->string) >= 0)
 220                                return 0;
 221                }
 222        }
 223
 224        if (data->ref_filters.nr) {
 225                struct string_list_item *item;
 226                int matched = 0;
 227
 228                /* See if any of the patterns match. */
 229                for_each_string_list_item(item, &data->ref_filters) {
 230                        /*
 231                         * Check all patterns even after finding a match, so
 232                         * that we can see if a match with a subpath exists.
 233                         * When a user asked for 'refs/tags/v*' and 'v1.*',
 234                         * both of which match, the user is showing her
 235                         * willingness to accept a shortened output by having
 236                         * the 'v1.*' in the acceptable refnames, so we
 237                         * shouldn't stop when seeing 'refs/tags/v1.4' matches
 238                         * 'refs/tags/v*'.  We should show it as 'v1.4'.
 239                         */
 240                        switch (subpath_matches(path, item->string)) {
 241                        case -1: /* did not match */
 242                                break;
 243                        case 0: /* matched fully */
 244                                matched = 1;
 245                                break;
 246                        default: /* matched subpath */
 247                                matched = 1;
 248                                can_abbreviate_output = 1;
 249                                break;
 250                        }
 251                }
 252
 253                /* If none of the patterns matched, stop now */
 254                if (!matched)
 255                        return 0;
 256        }
 257
 258        add_to_tip_table(oid, path, can_abbreviate_output);
 259
 260        while (o && o->type == OBJ_TAG) {
 261                struct tag *t = (struct tag *) o;
 262                if (!t->tagged)
 263                        break; /* broken repository */
 264                o = parse_object(&t->tagged->oid);
 265                deref = 1;
 266                taggerdate = t->date;
 267        }
 268        if (o && o->type == OBJ_COMMIT) {
 269                struct commit *commit = (struct commit *)o;
 270                int from_tag = starts_with(path, "refs/tags/");
 271
 272                if (taggerdate == TIME_MAX)
 273                        taggerdate = ((struct commit *)o)->date;
 274                path = name_ref_abbrev(path, can_abbreviate_output);
 275                name_rev(commit, xstrdup(path), taggerdate, 0, 0,
 276                         from_tag, deref);
 277        }
 278        return 0;
 279}
 280
 281static const unsigned char *nth_tip_table_ent(size_t ix, void *table_)
 282{
 283        struct tip_table_entry *table = table_;
 284        return table[ix].oid.hash;
 285}
 286
 287static const char *get_exact_ref_match(const struct object *o)
 288{
 289        int found;
 290
 291        if (!tip_table.table || !tip_table.nr)
 292                return NULL;
 293
 294        if (!tip_table.sorted) {
 295                QSORT(tip_table.table, tip_table.nr, tipcmp);
 296                tip_table.sorted = 1;
 297        }
 298
 299        found = sha1_pos(o->oid.hash, tip_table.table, tip_table.nr,
 300                         nth_tip_table_ent);
 301        if (0 <= found)
 302                return tip_table.table[found].refname;
 303        return NULL;
 304}
 305
 306/* may return a constant string or use "buf" as scratch space */
 307static const char *get_rev_name(const struct object *o, struct strbuf *buf)
 308{
 309        struct rev_name *n;
 310        struct commit *c;
 311
 312        if (o->type != OBJ_COMMIT)
 313                return get_exact_ref_match(o);
 314        c = (struct commit *) o;
 315        n = get_commit_rev_name(c);
 316        if (!n)
 317                return NULL;
 318
 319        if (!n->generation)
 320                return n->tip_name;
 321        else {
 322                int len = strlen(n->tip_name);
 323                if (len > 2 && !strcmp(n->tip_name + len - 2, "^0"))
 324                        len -= 2;
 325                strbuf_reset(buf);
 326                strbuf_addf(buf, "%.*s~%d", len, n->tip_name, n->generation);
 327                return buf->buf;
 328        }
 329}
 330
 331static void show_name(const struct object *obj,
 332                      const char *caller_name,
 333                      int always, int allow_undefined, int name_only)
 334{
 335        const char *name;
 336        const struct object_id *oid = &obj->oid;
 337        struct strbuf buf = STRBUF_INIT;
 338
 339        if (!name_only)
 340                printf("%s ", caller_name ? caller_name : oid_to_hex(oid));
 341        name = get_rev_name(obj, &buf);
 342        if (name)
 343                printf("%s\n", name);
 344        else if (allow_undefined)
 345                printf("undefined\n");
 346        else if (always)
 347                printf("%s\n", find_unique_abbrev(oid, DEFAULT_ABBREV));
 348        else
 349                die("cannot describe '%s'", oid_to_hex(oid));
 350        strbuf_release(&buf);
 351}
 352
 353static char const * const name_rev_usage[] = {
 354        N_("git name-rev [<options>] <commit>..."),
 355        N_("git name-rev [<options>] --all"),
 356        N_("git name-rev [<options>] --stdin"),
 357        NULL
 358};
 359
 360static void name_rev_line(char *p, struct name_ref_data *data)
 361{
 362        struct strbuf buf = STRBUF_INIT;
 363        int forty = 0;
 364        char *p_start;
 365        for (p_start = p; *p; p++) {
 366#define ishex(x) (isdigit((x)) || ((x) >= 'a' && (x) <= 'f'))
 367                if (!ishex(*p))
 368                        forty = 0;
 369                else if (++forty == GIT_SHA1_HEXSZ &&
 370                         !ishex(*(p+1))) {
 371                        struct object_id oid;
 372                        const char *name = NULL;
 373                        char c = *(p+1);
 374                        int p_len = p - p_start + 1;
 375
 376                        forty = 0;
 377
 378                        *(p+1) = 0;
 379                        if (!get_oid(p - (GIT_SHA1_HEXSZ - 1), &oid)) {
 380                                struct object *o =
 381                                        lookup_object(oid.hash);
 382                                if (o)
 383                                        name = get_rev_name(o, &buf);
 384                        }
 385                        *(p+1) = c;
 386
 387                        if (!name)
 388                                continue;
 389
 390                        if (data->name_only)
 391                                printf("%.*s%s", p_len - GIT_SHA1_HEXSZ, p_start, name);
 392                        else
 393                                printf("%.*s (%s)", p_len, p_start, name);
 394                        p_start = p + 1;
 395                }
 396        }
 397
 398        /* flush */
 399        if (p_start != p)
 400                fwrite(p_start, p - p_start, 1, stdout);
 401
 402        strbuf_release(&buf);
 403}
 404
 405int cmd_name_rev(int argc, const char **argv, const char *prefix)
 406{
 407        struct object_array revs = OBJECT_ARRAY_INIT;
 408        int all = 0, transform_stdin = 0, allow_undefined = 1, always = 0, peel_tag = 0;
 409        struct name_ref_data data = { 0, 0, STRING_LIST_INIT_NODUP, STRING_LIST_INIT_NODUP };
 410        struct option opts[] = {
 411                OPT_BOOL(0, "name-only", &data.name_only, N_("print only names (no SHA-1)")),
 412                OPT_BOOL(0, "tags", &data.tags_only, N_("only use tags to name the commits")),
 413                OPT_STRING_LIST(0, "refs", &data.ref_filters, N_("pattern"),
 414                                   N_("only use refs matching <pattern>")),
 415                OPT_STRING_LIST(0, "exclude", &data.exclude_filters, N_("pattern"),
 416                                   N_("ignore refs matching <pattern>")),
 417                OPT_GROUP(""),
 418                OPT_BOOL(0, "all", &all, N_("list all commits reachable from all refs")),
 419                OPT_BOOL(0, "stdin", &transform_stdin, N_("read from stdin")),
 420                OPT_BOOL(0, "undefined", &allow_undefined, N_("allow to print `undefined` names (default)")),
 421                OPT_BOOL(0, "always",     &always,
 422                           N_("show abbreviated commit object as fallback")),
 423                {
 424                        /* A Hidden OPT_BOOL */
 425                        OPTION_SET_INT, 0, "peel-tag", &peel_tag, NULL,
 426                        N_("dereference tags in the input (internal use)"),
 427                        PARSE_OPT_NOARG | PARSE_OPT_HIDDEN, NULL, 1,
 428                },
 429                OPT_END(),
 430        };
 431
 432        init_commit_rev_name(&rev_names);
 433        git_config(git_default_config, NULL);
 434        argc = parse_options(argc, argv, prefix, opts, name_rev_usage, 0);
 435        if (all + transform_stdin + !!argc > 1) {
 436                error("Specify either a list, or --all, not both!");
 437                usage_with_options(name_rev_usage, opts);
 438        }
 439        if (all || transform_stdin)
 440                cutoff = 0;
 441
 442        for (; argc; argc--, argv++) {
 443                struct object_id oid;
 444                struct object *object;
 445                struct commit *commit;
 446
 447                if (get_oid(*argv, &oid)) {
 448                        fprintf(stderr, "Could not get sha1 for %s. Skipping.\n",
 449                                        *argv);
 450                        continue;
 451                }
 452
 453                commit = NULL;
 454                object = parse_object(&oid);
 455                if (object) {
 456                        struct object *peeled = deref_tag(object, *argv, 0);
 457                        if (peeled && peeled->type == OBJ_COMMIT)
 458                                commit = (struct commit *)peeled;
 459                }
 460
 461                if (!object) {
 462                        fprintf(stderr, "Could not get object for %s. Skipping.\n",
 463                                        *argv);
 464                        continue;
 465                }
 466
 467                if (commit) {
 468                        if (cutoff > commit->date)
 469                                cutoff = commit->date;
 470                }
 471
 472                if (peel_tag) {
 473                        if (!commit) {
 474                                fprintf(stderr, "Could not get commit for %s. Skipping.\n",
 475                                        *argv);
 476                                continue;
 477                        }
 478                        object = (struct object *)commit;
 479                }
 480                add_object_array(object, *argv, &revs);
 481        }
 482
 483        if (cutoff)
 484                cutoff = cutoff - CUTOFF_DATE_SLOP;
 485        for_each_ref(name_ref, &data);
 486
 487        if (transform_stdin) {
 488                char buffer[2048];
 489
 490                while (!feof(stdin)) {
 491                        char *p = fgets(buffer, sizeof(buffer), stdin);
 492                        if (!p)
 493                                break;
 494                        name_rev_line(p, &data);
 495                }
 496        } else if (all) {
 497                int i, max;
 498
 499                max = get_max_object_index();
 500                for (i = 0; i < max; i++) {
 501                        struct object *obj = get_indexed_object(i);
 502                        if (!obj || obj->type != OBJ_COMMIT)
 503                                continue;
 504                        show_name(obj, NULL,
 505                                  always, allow_undefined, data.name_only);
 506                }
 507        } else {
 508                int i;
 509                for (i = 0; i < revs.nr; i++)
 510                        show_name(revs.objects[i].item, revs.objects[i].name,
 511                                  always, allow_undefined, data.name_only);
 512        }
 513
 514        UNLEAK(revs);
 515        return 0;
 516}